Body temperature taken immediately after awakening in the morning and before getting out of bed. Typically, the BBT is used by women to identify the days during the menstrual cycle when ovulation (the release of an egg from the ovary) takes place. A woman’s temperature often falls by a few tenths of a degree during the 12 to 24 hours before ovulation; then, it rises for several days after ovulation. By measuring the BBT with a special thermometer that is able to detect slight changes and by recording the temperature on a chart every day for several months, an ovulation pattern can be detected. A woman is most likely to become pregnant if she has sex on the days just before, after, or on the day of ovulation. ovulation. Tracking of the BBT can be used by women who are trying to become pregnant or by women who want to avoid becoming pregnant.
Temperature of the body fully at rest, such as first thing in the morning, before any activity.
The body’s temperature when in a state of complete rest.